#ifndef _SET_H_
#define _SET_H_

#include <stdlib.h>

#define SET__SIZE 256

struct set {
    char s[SET__SIZE];
};

struct set set__empty(void);
int        set__is_empty(const struct set *);
size_t     set__size(const struct set *);
int        set__find(const struct set *, char);
int        set__add(struct set *, char);
int        set__remove(struct set *, char);
int        set__inter(const struct set * s1, const struct set * s2, 
		      struct set * si);
int        set__union(const struct set * s1, const struct set * s2, 
		      struct set * su);

#endif
